Title :
Mechanism of Gm degradation and comparison of Vt instability and reliability of HfO2, HfSiOx and HfAlOx gate dielectrics with 80 nm poly-Si gate CMOS
Author :
Tseng, H.-H. ; Grant, J.M. ; Hobbs, C. ; Tobin, P.J. ; Hebert, L. ; Ramon, M. ; Kalpat, S. ; Wang, F. ; Triyoso, D. ; Gilmer, D.C. ; White, B.E. ; Abramowitz, P. ; Moosa, M. ; Luo, Z. ; Ma, T.P.
Author_Institution :
Adv. Product R&D Lab., Freescale Semicond., Austin, TX, USA
Abstract :
To achieve a lower gate leakage in high speed devices at the same equivalent oxide thickness, a major thrust is to replace the SiO2 with a thicker dielectric that has a higher dielectric constant. Recently, there has been much interest in hafnium dioxide as a potential high-k gate dielectric as presented in E. P Gusev et a. (2001), B. Barlage et al. (2001), G. Wilk et al. (2001), C. Hobbs et al. (2001), W. Zhu et al. (2001), W. Qi et al. (2000) and B. Lee et al. (1999) due to its high permittivity. However, the polycrystalline microstructure may be undesirable. In order to increase the crystallization temperature, SiO2 or Al2O3 are added to HfO2 to form Hf silicates atid Hf aluminates. A systematic study to compare the device characteristics of these three major candidates is needed. In this work, we have compared them in terms of the key challenges of high-K devices such as Gm degradation, Vt instability, and reliability, in devices fabricated with a conventional CMOS process technology according to A. Perera et al. (2000).
Keywords :
CMOS integrated circuits; aluminium compounds; dielectric materials; hafnium compounds; integrated circuit reliability; permittivity; silicon compounds; 80 nm; CMOS process technology; Gm degradation; HfAlO; HfO2; HfSiO; Vt instability; crystallization temperature; device characteristics; device reliability; dielectric constant; equivalent oxide thickness; high speed devices; high-k gate dielectric; polycrystalline miciostructure; Crystallization; Degradation; Dielectric devices; Gate leakage; Hafnium oxide; High K dielectric materials; High-K gate dielectrics; Microstructure; Permittivity; Temperature;
Conference_Titel :
VLSI Technology, 2005. (VLSI-TSA-Tech). 2005 IEEE VLSI-TSA International Symposium on
Print_ISBN :
0-7803-9058-X
DOI :
10.1109/VTSA.2005.1497110